# Performance and muscle peptides

> Source: https://peptidewellnessusa.com/peptides/performance/
> Category
> By PeptideWellness Editorial Team · Medically reviewed by Ksenia Petrushkina, PA-C, MPAS · Updated November 9, 2026

GH secretagogues — Ipamorelin, CJC-1295, MK-677 — and adjacent GHRH analogs used for lean mass, recovery, and body composition. Stack mechanics, what the trials show, and the honest read on risks.

The peptides sold for muscle growth are growth-hormone secretagogues: ipamorelin, CJC-1295 and their stacks, with MK-677, a pill that acts on the same receptor as ipamorelin but is not a peptide. None is FDA-approved to build muscle, and no controlled trial has shown them adding muscle in healthy adults over the long term; the established treatment for a true growth-hormone deficiency is growth hormone itself, not these.

Performance peptides are the category most clearly defined by what they are not. They are not FDA-approved drugs. They are not part of any standard endocrinology guideline for "body composition optimization" in non-deficient adults. They are not legally usable by athletes subject to WADA-aligned testing. They are growth-hormone secretagogues sold through compounding pharmacies and research-chemical channels. Recreational lifters and bodybuilders use them off-label, anti-aging and hormone-optimization clinics occasionally prescribe them, and sports-medicine reviews consistently flag them as a class where the marketing has outrun the trial evidence. This page lays out the actual pharmacology, the actual evidence, and the actual risks.

## What is actually approved

**No GH secretagogue is FDA-approved for human use as a body-composition or performance enhancer.** The only FDA approval in the broader secretagogue class is **capromorelin**, and only as a veterinary drug: Entyce and Elura are ghrelin receptor agonists approved for appetite stimulation in dogs and cats. Capromorelin reached phase 2 trials in humans for elderly frailty and recovery from hip-fracture surgery in the early 2000s but did not progress to FDA approval for humans.

Within our compound set:

- **CJC-1295** (long-acting GHRH analog) is not FDA-approved. The original sponsor (ConjuChem) ran phase 2 trials in the mid-2000s; development was discontinued before any approval pathway closed.
- **Ipamorelin** (selective GHRP, ghrelin-receptor agonist) is not FDA-approved. Development by Novo Nordisk in the early 2000s for postoperative ileus and elderly hip-fracture recovery did not advance to a US approval.
- **MK-677 (ibutamoren)**, an oral ghrelin-receptor agonist, is not in our canonical compound list but is mentioned in the category deck. It is also not FDA-approved, despite Merck's substantial early development program for sarcopenia and pediatric short stature.

These compounds reach US patients almost exclusively through **503A compounding pharmacies** on physician prescription or through **research-chemical suppliers** that operate outside the prescription system. The compounding pathway carries the same regulatory architecture as the recovery and longevity categories — see our [compounded vs branded peptides explainer](https://peptidewellnessusa.com/learn/compounded-vs-branded/) for the legal framework.

## CJC-1295 — mechanism, history, and what the half-life debate means

CJC-1295 is a synthetic analog of growth-hormone-releasing hormone (GHRH). The native GHRH protein has a serum half-life of approximately 7 minutes — too short to be practical as a therapeutic. CJC-1295 modifies the GHRH sequence at four positions and (in the DAC variant) attaches a maleimidopropionic-acid linker that allows the molecule to bind irreversibly to circulating albumin. The albumin binding extends the effective half-life to roughly 7-8 days.

**Two variants in the market — different pharmacokinetics.** "CJC-1295 with DAC" (Drug Affinity Complex) has the long half-life and produces a sustained GHRH-receptor stimulation for days after a single dose. "CJC-1295 without DAC" (also called Mod GRF 1-29) lacks the albumin linker and reverts to a roughly 30-minute half-life — much closer to native GHRH. Marketing copy and even peer-reviewed papers occasionally conflate the two, but the pharmacokinetic difference is substantial. The original ConjuChem clinical program studied the DAC variant; most "CJC-1295" sold by compounding pharmacies and research suppliers in 2026 is also the DAC variant unless explicitly stated otherwise.

The original ConjuChem phase 2 trials in adults with HIV-associated lipodystrophy were not completed to an FDA filing. The CJC-1295 program was discontinued in the late 2000s in the course of broader ConjuChem corporate restructuring and was not subsequently revived. There is no large modern phase 3 human RCT of CJC-1295.

## Ipamorelin — selective GHRP, stacked with GHRH analogs

Ipamorelin is a selective growth-hormone-releasing peptide (GHRP) acting on the ghrelin receptor (GHS-R1a). Compared with earlier GHRPs (GHRP-2, GHRP-6) it has a cleaner selectivity profile — minimal effect on cortisol, prolactin, or appetite at typical doses. The original development by Novo Nordisk targeted postoperative ileus and recovery from hip-fracture surgery in elderly patients; the program did not advance to FDA approval.

Ipamorelin is typically stacked with a GHRH analog (CJC-1295 with or without DAC, or tesamorelin in some protocols) on a simple rationale: a GHRH receptor agonist plus a separate ghrelin receptor agonist should produce a GH pulse larger than either compound alone. The mechanism rationale is sound; the clinical evidence supporting the stacking strategy in adults without GH deficiency is preclinical-and-observational, not controlled-trial-grade.

## What the trials show — and what they do not

The 2020 Translational Andrology and Urology review by Vij and colleagues is the cleanest published summary of GH secretagogue use in body composition management in hypogonadal males [1]. The 2026 American Journal of Sports Medicine primer [2], the 2026 JAAOS Global Research Reviews paper [3], and the 2026 Sports Medicine (Auckland) review [4] each cover GH secretagogues within the broader unapproved-peptide landscape and reach similar conclusions. The mechanism is well-mapped, and the preclinical and short-term physiologic data are consistent. The long-term controlled-trial data for body-composition outcomes in non-deficient adults are limited, and the safety record at typical off-label doses is empirical rather than systematic.

A 2022 Experimental Physiology case report of LGD-4033 (a selective androgen receptor modulator, not a peptide) combined with MK-677 use documented measurable body-composition changes alongside biomarker shifts. It is a useful real-world data point, but a case report, not a controlled trial [5].

What is consistent across the modern reviews: **the use case for GH-axis pharmacotherapy in adults with documented adult-onset GH deficiency is medically established** (with recombinant human GH, not secretagogue peptides). **The use case for GH secretagogues in non-deficient adults for body-composition optimization is not.** The 2026 Sports Medicine review is explicit that the recreational and bodybuilding use case operates ahead of the controlled-trial evidence [4]. The 2026 J Sports Med Phys Fit critical review documents the broader doping context [6].

## WADA prohibition

**All GH secretagogues — including CJC-1295, ipamorelin, MK-677, and the GHRH analogs sermorelin and tesamorelin — are prohibited at all times under the WADA Prohibited List** [7], in the S2 category (Peptide Hormones, Growth Factors, Related Substances and Mimetics). The prohibition applies in-competition and out-of-competition. Athletes subject to WADA-aligned testing — NCAA student-athletes via USADA, Olympic-pathway athletes, professional athletes in WADA-aligned sports — face anti-doping sanction for use regardless of medical justification or compounding-pharmacy provenance.

The 2026 J Sports Med Phys Fit critical review documents the established pattern of GH-secretagogue use in recreational and professional sport [6]. The WADA detection methodology has improved substantially over the past five years; reliance on "undetectable" framing is not supported by the current testing literature.

## Safety considerations

Three points worth flagging.

**IGF-1 elevation is the proximal effect, and it is dose-dependent.** GH secretagogues increase pituitary GH release; GH in turn drives hepatic IGF-1 production. Sustained IGF-1 elevation has known associations with several cancer-progression pathways at the molecular level, and acromegaly (chronic GH excess) is associated with elevated cancer risk in observational studies. Whether the IGF-1 elevations produced by typical off-label secretagogue dosing approach the chronic-acromegaly range is dose-dependent and individual; serum IGF-1 monitoring is the standard precaution.

**Glucose dysregulation is a class effect.** GH antagonizes insulin action; chronic elevation can worsen insulin sensitivity. Patients with prediabetes or type 2 diabetes who use GH secretagogues should monitor fasting glucose and HbA1c.

**Concomitant SARM use compounds the risk picture.** The 2022 Experimental Physiology case report [5] documents a use pattern (LGD-4033 plus MK-677) that pairs androgen-receptor modulator effects with GH-axis effects. Stacking unapproved peptides with unapproved selective androgen receptor modulators amplifies the unknowns and is a pattern repeatedly flagged in the sports-medicine literature.

## Where to find these compounds

Of the telehealth providers PeptideWellness covers in our [reviews](https://peptidewellnessusa.com/providers/), the platforms with the most relevant performance-category programs are [Maximus](https://peptidewellnessusa.com/providers/maximus/) (sermorelin and GH peptides as part of the men's-performance menu) and [TeleZenMD](https://peptidewellnessusa.com/providers/telezenmd/) (sermorelin and a broader peptide menu). For Maximus's regulatory record, see our [news coverage](https://peptidewellnessusa.com/news/fda-warning-letters-compounded-glp-1-june-2026/) of the FDA's June 2026 enforcement action against its GLP-1 marketing. The growth-hormone-axis cross-tag below this section lists the other category landings where related compounds appear.

## Frequently asked

### Are CJC-1295 and ipamorelin safe for adults without GH deficiency?

The empirical safety record at typical off-label doses is generally tolerated. Controlled-trial safety data for the body-composition use case in non-deficient adults is limited. Monitoring IGF-1 levels and fasting glucose is standard precaution.

### Will using GH secretagogues fail a sports drug test?

Yes if you are subject to WADA-aligned testing. All GH secretagogues including CJC-1295, ipamorelin, MK-677, sermorelin, and tesamorelin are on the S2 prohibited-substance category at all times [7]. Modern detection methods are reliable enough that "undetectable" claims should be treated skeptically.

### What is the difference between CJC-1295 with DAC and without DAC?

The DAC (drug affinity complex) variant binds to albumin and has a half-life of about a week. The non-DAC variant (Mod GRF 1-29) has a half-life around 30 minutes. Different pharmacokinetics, different dosing protocols. Sellers do not always distinguish the two; for the right protocol you should know which you are receiving.

### Is MK-677 a peptide?

No. MK-677 (ibutamoren) is an orally bioavailable small molecule, not a peptide. It acts on the same ghrelin receptor as ipamorelin but is a structurally different compound. It is similarly not FDA-approved and similarly WADA-prohibited.

### Is recombinant human growth hormone (rhGH) a better alternative?

For diagnosed adult-onset GH deficiency, rhGH is the FDA-approved standard of care under appropriate endocrinology supervision. For non-deficient adults seeking "anti-aging" or body-composition effects, rhGH is illegal to prescribe in the US under the 1990 Anabolic Steroid Control Act unless for a specifically approved indication. Secretagogue use does not change the underlying clinical question — there is no FDA-recognized indication for GH augmentation in non-deficient adults seeking body-composition outcomes.

## References

1. [Vij SC, Kashanian JA, Helo S, et al. Beyond the androgen receptor: the role of growth hormone secretagogues in the modern management of body composition in hypogonadal males. *Transl Androl Urol.* 2020;9(Suppl 2):S149-S159. PMID 32257855.](https://pubmed.ncbi.nlm.nih.gov/32257855/)
2. [Injectable Peptide Therapy: A Primer for Orthopaedic and Sports Medicine Physicians. *Am J Sports Med.* 2026. PMID 41476424.](https://pubmed.ncbi.nlm.nih.gov/41476424/)
3. [Therapeutic Peptides in Orthopaedics: Applications, Challenges, and Future Directions. *J Am Acad Orthop Surg Glob Res Rev.* 2026. PMID 41490200.](https://pubmed.ncbi.nlm.nih.gov/41490200/)
4. [Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance. *Sports Med.* 2026. PMID 41966639.](https://pubmed.ncbi.nlm.nih.gov/41966639/)
5. [LGD-4033 and MK-677 use impacts body composition, circulating biomarkers, and skeletal muscle androgenic hormone and receptor content: A case report. *Exp Physiol.* 2022. PMID 36303408.](https://pubmed.ncbi.nlm.nih.gov/36303408/)
6. [A new era of doping? Use of peptide and peptide-analog drugs in recreational and professional sport and bodybuilding: a critical review. *J Sports Med Phys Fit.* 2026. PMID 41880199.](https://pubmed.ncbi.nlm.nih.gov/41880199/)
7. [World Anti-Doping Agency — Prohibited List.](https://www.wada-ama.org/en/prohibited-list)

> Editorial note: Informational only — not medical advice. Decisions about GH-axis pharmacotherapy should be made with a clinician familiar with endocrinology, anti-doping testing exposure, and the patient's metabolic risk profile. Last reviewed June 2026.

## What we cover under performance.

- [CJC-1295](https://peptidewellnessusa.com/peptides/cjc-1295/) — GHRH analog (long-acting) · Sustained GH release · 3-5 weeks
- [IGF-1 LR3](https://peptidewellnessusa.com/peptides/igf-1-lr3/) — IGF-1 analogue, 83 aa · Lab research tool; no human data · No human data
- [Ipamorelin](https://peptidewellnessusa.com/peptides/ipamorelin/) — GH secretagogue · Lean mass, recovery · 2-4 weeks